#include <iostream>
#include <cstdio>
using namespace std;

int main()
{
 int n;
 cin >> n;
 int sum = 0;
 int t;
 double ret = 0;
 int tmp = n;
 while(tmp--)
 {
 	cin >> t;
 	sum+=t;
 }
 ret = sum*1.0/n;
 printf("%.2f",ret);
 
   
   		
}

